The workaround for this, and/or the cause, is that your not the owner for the Oracle Windows software. Because the new software install magically removed my Listener Windows Service, I also couldn’t start the Listener process via the Windows Service Manager program. To get it back, that is start the listener and create the appropriate correct Listener service where the ownership matches the oracle software (& database instances), you will have to create a command (.cmd) or batch (.bat) file with something along the lines of…

lsnrctl start

pause

After executing this file via “Run as Administrator“, you will be asked the password for the user that owns the software, in my case “oracledb”

C:\Windows\system32>lsnrctl start

LSNRCTL for 64-bit Windows: Version 12.1.0.2.0 – Production on 07-DEC-2015 10:34:01

Copyright (c) 1991, 2014, Oracle. All rights reserved.

Starting tnslsnr: please wait…

Enter oracledb’s password :

TNSLSNR for 64-bit Windows: Version 12.1.0.2.0 – Production
Log messages written to C:\Oracle\database\diag\tnslsnr\8s98y52\listener\alert\log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=8s98y52)(PORT=1521)))